Envelope making method and mechanism



v. E. HEYWOOD 2,772,611

ENVELOPE MAKING METHOD AND MECHANISM- 5 Sheets-Sheet 1 Dec. 4, 1956 Filed June 16 1951 INVENTOR VINCENT E. HEYWOOD ATTORNEY Dec. 4, 1956 Filed June 16, 1951 v. E. HEYWOOD 2,772,611

ENVELOPE MAKING METHOD AND MECHANISM 5 Sheets-Sheet 2 INVENTOR Y ATTORNEY Dec. 4, 1956 v. E. HEYWOOD ENVELOPE MAKING METHOD AND MECHANISM 5 Sheets-Sheet 3 Filed June 16, 1951 INVENTOR vmctu'r zmzwlooo BY ATTORNEY Dec. 4, 1956 v. E. HEYWOOD ENVELOPE MAKING METHOD AND MECHANISM 5 Sheets-Sheet 4 Filed June 16,' 1951 I A fi 1 v v E I 1 1 0 Q q l o u h INVENTOR VINCENT E. NEYWOOD WWW ATTORNEY Dec. 4, 1956 v. E. HEYWOOD 2,772,611

ENVELOPE MAKING METHOD AND MECHANISM 5 Sheets-Sheet 5 Filed June 16, 1951 mvea'roa VINCENT I .HEYWO OD ATTORNEY United States Patent ENVELOPE MAKING METHOD AND MECHANISM Vincent E. Heywood, Worcester, Mass., assignor to United States Envelope Company, Springfield, Mass., a-corporation ofTMaine- Application. June 16, 1951, Serial No. 231,950

49'Claims. (CI. 93-62) This application is-a continuation-in-part of my. copending application for Method of Manufacturing Envelopes, filed April 2,. 1949 as Serial No.. 85,133, which was al.-- lowed' December 6, 1951, and is now abandoned.v

This invention relates in general to envelope manufacture, and in particular to new and highly adlvanta: geousmethods andmeans for applying to successive envelope blanks, during their rotary machine. manufacture. into envelopes, the adhesive areas which, in each. completed' envelope, serve respectively (1') to stick the seams of its pocket-forming flaps, and (2) tosupply the. usual wettable coating of sealing'jgum or glue on its pocketclosirigfflap, frequently ed. the seal flap.

Modernenvelope-mak ng inachines of'the rotary type, especially those used for-making triangular flap or diagonal seam envelopes, have output capacities, or rates of envelope. production, in a range of from 250 to 350 envelopes per minute. However, an envelope production rate in this range (250 to 350' envelopes per minute). is very far. below (actually several times lower than) the rate. at which it is practicable and feasible, in any such rotary machine,.t'o perform on the successive blanks in process, the two flap-folding operations which are essential to their conversion into envelopes, these operations being an initial infolding of each blanks side flaps, and a subsequent folding, over of its back or bottom flap into adhesive seam connection with its side flaps.

Furthermore, an envelope production rate in the above. stated range (250 to 350' envelopes per minute) is also very far below (actually many times lower than) the. rate at which it is practicable and feasibie to gum or glue the successive blanks trailingseal' flap margins, in any trifugal' force (which is directly proportional to the square off the speed). has. always been the significant limiting factor, inevery rotary machine, on the permissible. speed. of blank movement. therethrough, and thus has been an ever-effective. bottleneck on the envelope production rates: of all: such machines. That is to say, whenever a conventional rotary machine is speeded. up, to appreciably exceed. its factory-rated outputcapacity (ofI250 to 3.5.0 envelopes. per minute), tiny glue particles in. a mist or spray, which are thrown off centrifugally by the speeded-up seam. glue imprinting device, will always accumulate on nearby blank contacting: machine surfaces exposed between the passing spaced. apart blanks, to quickly foul up the machines operation and necessitate its. stoppage.

By the same token, a second production bottleneck of exactly the same nature as described above, has been. present in all prior rotary envelope-making machines which are requiredlto. supply the blanks seal flap margins.

with shaped or. contoured areas. of Visible. gumrning, nonuniform in width. For, as stated. in the aforesaid United States Patent No.. 2,132,227, the coating or spreading process of. seal flap gumming can never be. used for this shaped or contoured gumrning of seal flap margins. Instead, in any such rotary machine, the successive blanks. in order to receive these shaped or contoured areas of seal flap. gumrning, have always been moved in spacedapart relation, past a. second. rotary glue imprinting device, rotating at thesame high speed as the above mentioned seam. glue imprintingw device, and thereby imposing the same limitation. as. the latter, on permissible blank speed. through. the machine, and accordingly onrotary machine which employs, for the progressive en,

masse gumrning of said margins, the so-called coating or spreading process of' seal flap gumming. This process, used in numerous rotary machines, is old andv well known in the art, being shown and described in United States Patent No; 2,132,227 of Winkler et all, and in many other patents.

But these long-existing potentialities of numerous prior rotary machines for very much higher rates of envelope production, afforded alike by this coating or spreading process of seal. fiap gumrning, and by the very rapid rates at which the two essential flap folding operations can be performed, have heretofore gone entirely for naught, and have never been of the slightest avail or benefit. This is because of the fact that elsewhere, in every rotary envelope-making machine, the successive blanks, in order to receive their seam-sticking glue, have alwaysbeen moved in spaced relation past the usual rotary seam glue imprinting device, at the very highest blank. speeds (250 to 350 blanks per minute), at which are performed thereon the two essential flap folding operations. Under these conditions, with said seam glue imprinting device needing to rotate in step with. this highest speed of blank movement through the machine, the effect on said rotary seam glue imprinting device of cenwhich exposes eachblanks seam glue receiving side flap margins in-close proximity to the adjacent blanks seal flap margin; and since the. blank speed established by this shingl'ing operation. is always very appreciably lower than the highest blank. speed at which the twoessential flap folding operations. are performed, the glue imprint-- ing device or devices,. rotating in. step with this blank assemblys reduced speed, will. not reach a speed at which. any centrifugal throw off of glue takes place, until said. highest blank speed (which determines the envelope production ratev of. the machine) is far in excess (frequently two or three times greater than) the highest blank speedv (of 25.0 to 350 blanks per minute) that has heretofore been. the ceiling or limit of achievement, in conventional, rotary envelope-making machines: This fact, coupledwith the ability of the shingled' blank assembly to. cope successfully, as hereinafter described, with considerable. centrifugal glue throw-off from the imprinting, device or devices, makes it' possible, in the rotary machine manufiacture of envelopes, to reach production'ratesas high as. 900 or 1000 envelopes per minute.

These extremely highrates of envelope production can be obtained with any blanks, regardless of shape or outline, such as are employedfor the manufacture. of the familiar diagonal. seam on.triangular flap envelopes, as well as of double side seam envelopes. Butwith substantially rhombic (including substantially square) blanks, this invention obtains, over and above its outstanding achievement of drastically increased rates of envelope production, an equally far-reaching. advantage in the ease, economy and simplicity with which it secures the very highest quality and perfection of the shaped or contoured seal flap gumming of each blank.

In that respect, as regards prior rotary machines adapted for shaped or contoured seal flap gumming, the demand that these shaped or contoured glue imprints shall extend fully and uniformly in every case to the extreme or utmost edge of each envelopes seal flap, has generally been met by resort to overgumming, i.e. arranging for the shaped rotary seal glue imprinting die or segment to slightly overlap each seal flap edge, with resulting deposit of its excess glue at every imprinting operation, on an underlying platen roller. Thus, in all such overgumming operations heretofore performed, elaborate provisions have had to be made (as described in my Patent No. 2,568,629 of September 18, 1951) for washing off this excess glue, after each and every imprinting action of the die, to prevent such glue from being smeared by the platen roller onto the surfaces of subsequently following blanks. All such glue thus washed off has of course been entirely wasted and has never been reclaimable.

The instant invention eliminates entirely these wasteful and complicated procedures of previous overgumming practice, when operating on substantially rhombic (including substantially square) blanks, being blanks whose seal flap edges have the same angularity as the lower edges of their infolded side flaps. This is because the selfsame shallow shingling operation which exposes in close proximity the two different glue receiving areas of adjacent blanks. is availed of, in the case of these symmetrical blanks, to establish a very slight overlap of each blanks trailing seal flap edge upon the parallel lower edges of the next blanks infolded side flaps. Under these conditions, when the invention employs, for the shaped or contoured gumming of the successive seal flap margins of the slow speed blank assembly, a conventional rotary overgumming glue imprinting die or segment, the latters excess glue, instead of being wasted, and needing at each imprinting operation to be washed off, is imprinted along said overlaps upon adjacent marginal areas of the next blanks infolded side flaps, where it serves in every case as the seam sticking media of the envelope produced from said next blank.

Other and further advantages of the invention will be apparent from the following detailed description thereof, taken in connection with the accompanying drawings. These drawings, for depicting the invention in its most advantageous light, show its use with blanks of substantially rhombic or diamond shape, in order to reap all of the benefits, above set forth, from the use of a shingle two-purpose rotary glue imprinting device which, in the act of over-gumming each seal flap margin, provides the seam sticking glue for the next blank.

But wholly apart from this achievement (with blanks of certain shapes), of seal flap overgurnming, in the entire absence of any glue wastage or any glue wash off complication, the invention effectually overcomes, for seam glue imprinting and for contoured seal flap gumming of triangular flap blanks of practically any shape, the very restrictive production bottlenecks which have heretofore always existed in conventional rotary envelope making machines. Thus any such rotary machines to which the principles of this invention are applied can be operated to give rates of envelope production two or three times greater than the rates (250 to 350 envelopes per minute) which have heretofore been recognized as the maximum envelope output capacities of such mahines.

In the accompanying drawings:

Fig. 1 is a diagrammatic view, illustrating, in sequence from right to left, certain of the operations that are performed by my invention on the envelope blanks in process.

Fig. 1a is a diagrammatic view illustrating one method of producing such blanks.

Fig. 2 is a top plan view of certain mechanism embodying my invention.

Fig. 3 is a side elevation of the mechanism of Fig. 2.

Fig. 4 is a sectional view on line 44 of Fig. 2.

Fig. 5 is a view similar to Fig. 2, but with upper parts, above the plane of blank travel, removed.

Fig. 6 is a large scale view of the two-purpose overgumming rotary glue imprinting device which is used with substantially rhombic blanks.

Like reference characters refer to like parts in the different figures.

The drawings show my invention as applied to the manufacture of envelopes from a succession of substantially diamond-shaped blanks, each of which, as indicated at A, Fig. 1, consists of a rectangular body portion 1, having opposite similar side flaps '2, 2 and opposite similar bottom and seal flaps 3 and 4 respectively. A succession of such flat blanks A, A may be fed one by one from a supply stack, not shown. Or, such blanks may be continuously produced, as indicated diagrammatically in Fig. 1a, for concurrent delivery to and fabrication in the mechanism of this application, by successive diagonal cutoffs of a traveling paper web followed by suitable notchings 5 and trimmings 6 of the severed diamond shaped pieces, substantially as described in my United States Patent No. 2,696,255 of December 7, 1954, Blank- Forming Method and Mechanism for Envelope Making Machines.

In any case, the successive blanks A are forwarded flatwise, initially in spaced relation, in a direction (arrow X, Fig. 1) at right angles to the extension therefrom of their side flaps 2, 2, such movement (produced by any suitable rollers, belts, or the like, not shown) carrying the successive spaced blank-s A in turn past suitable side flap folders 7, 7, shown diagrammatically in Fig. 1 as of the conventional plowshare type. Such folders Operate in a manner well known in the envelope-making art, to fold over each moving blanks side flaps 2, 2 against its body portion 1, as shown at B, Fig. 1. In this partly-folded substantially six-sided condition, the successive spaced partly-folded blanks B, moving parallel (arrow X, Fig. 5) to their side edge folds 8, 8 are delivered one by one in rapid succession to the right-hand end of the mechanism illustrated by Figs. 2, 3, 4 and 5 hereof, through which said blanks continue their flatwise advance, substantially in the plane of the line Y, Y of Fig. 3, and in the par ticular manner now to be described.

The mechanism illustrated by Figs. 2, 3, 4 and 5 has longitudinal side frame members 9, 9 which provide support at their right-hand ends for cooperating upper and lower high speed blank forwarding rolls 10 and 1.1, the latter at its central portion being of reduced diameter,

- as shown at 12, for a purpose to be hereinafter described.

Said lower roll 11 is here shown as secured to a suitably journalled drive shaft 13 whose rotation may be derived, through gearing not shown, from that of the preceding rolls or other forwarding means that deliver the successive spaced partly-folded blanks B to the rolls 10 and 11. Said shaft 13 carries a gear 14 with which meshes a gear 15 on the upper roll 10, whereby the two rolls 10 and 11 are rotated in unison so as to imp-art to each blank delivered thereto a leftward movement at relatively high speed.

'For continuing such initial high speed blank movement, but preferably by engagement only with the outside edge folds 8, 8 of each blank, the mechanism provides, adjacent to rolls 10, 11, two laterally spaced pairs of narrow upper and lower blank forwarding rolls 16, 17 whose respective shafts 18 and 19 are suitably journalled in the side frame members 9, 9. Said shafts carry intermeshing gears 20 and 21 respectively, the latter of which is driven from shaft 13 in the desired counterclockwise direction by means of an interposed idler gear 22 (Fig. 4) that meshes with the gear 14 on drive shaft 113. The peripheral or surface speeds of the spaced pairs of naranswers 5 row [[0115 16, 17 are suchthat the initially imparted high: speed. blank feed-in movement is maintained; during the bight of. said rolls on; each blanks' side edge. fields 8', '8. However, it is to be noted. that each upper roll -16 is relieved, as shown at 23', Fig; 4, for somewhat over 90" of its periphery, so as to discontinue the high speed propulsion by said rolls 1'6, 17 of any such; partly-folded blank B, when it has moved far enough leftward for its side edge folds 8, '8 to come under the influence of the next-encountered blank forwarding devices, which, as hereinafter described, are adapted to continue each blanks leftward movement at a greatly reduced. speed which is approximately only one-half of its former speed.

This abrupt slowdown of each blanksv leftward movement. is accomplished by spaced pairs of narrow upper and lower feeding rolls 24, 25,. which are preferably operative, like the pairs of rollers 16 and 1 7, on the side edge folds 8, 8 of each blank. The respective shafts 26 and 27 of rolls 24 and 25 are suitably journal-led in the side frame members 9, '9 and carry intermeshing gears 28 and 29 respectively. As best shown. inFigs; 4 and 5, an extension of high speed shaft 19 carries a. pinion 30 which, through an idler gear 31, drivesa large gear 32 carried by an extension 'of shaft. 27, whereby to rotate said shaft 27 in the desired counterclockwise direction at approximately one-half the speed of the shaft 19. Thus each partly-folded blank, after having been moved leftward at the initial high speed of blank. feed-in to the approximate position represented at B, Fig. 5, has its speed of leftward movement cut approximately in: half when its side edge folds 8, '8 encounter the-pairs of slow speed rolls 24, 25. In this connection it is to be noted that each upper roll 24 is relieved, as shown at 33, 33 on its periphery, in a manner so related angularly to the reliefs 23 of the high speed rolls 16, that the transition from. high speed blank movement to low speed blank movement is always accomplished smoothly, withoutnany buckling of the blank.

This speed reduction obtains in. every case-the. partial overtaking of each partlyfolded blank. by the next fol lowing blank, and this of course regardless of the bl-anks shape, or whether with triangular flap blank-s, as. provided for manufacture into diagonal seam envelopes, the blanks are of the illustrated substantially rhombic shape, or are of some variant shape, for instance with L back flaps considerably deeper than their sea-l flaps. In the case of any triangular flap blanks, this partial overtaking causes overlapping of the successive blanks in such a manner as to bring leading side flap edges 34, 34-

of each following blanks infolded side flaps into close (approximately at position B, Fig. -5), at which time the apex 37 of its trailing seal flap- '4 is about to be quickly overtaken by the apex 38- of the fast moving next blanks leading back or bottom flap B.

To avoid any possibility of collision between. such. respective blank apexes 37 and 38, and to insure passage of the latter beneath the former, the reduced portion 12 of high speed roll .11 is. equipped, as herein. shown, with a leaf spring member 39, fastened at its forward. end: to said reduced portion 12 land with its free end projecting slightly beyond the effective periphery of roll 11,. in an angular position such as to-give a slight upward kick to each slow moving seal flap apex 37, just before it is overtaken by the fast moving bottom flap apex 38 of the next blank. In this way it is made certain that each leading apex 38 will always be projected beneath the slowed- This exposure in juxtaposed relation 6 down blankf'sv trailing apex 37;, in: the manner indicated at'GlinFig; 1..

The abovedescribed slow down of each blank by rolls 24 2'5 enables the next following blank, advancing at high speedi to have this. overtaking action relative to the slower moving preceding blank until such followingblank has its own speed sharply reduced from seizure of its side edge folds 8, 8 by said slow speed rolls 2'4, 25.. This seizure: is arranged in every case to occur, just as the following'blankk leading side flap edges 34, 34 catch up with. 'or overtake the trailing seal flap edges 3'5, 35 of the. preceding: slowed down blank. ln other words, referring to Fig-5, during thetime that any partlyfo'lded blank is moving at slow speed from approximate position B to: approximate position B the following partly fo-lded' blank (from approximate position B, Fig. 5'):- will be moving by virtue: of its high feed-in speed, as continued by high speed rolls 10, 11 and 16, I7, approximately twice as. far or into position B", at approximately which point it takesover theslow speed of the precedinggblank, andcontinu'esthereafter to move at such slow speed, in. unison with said preceding blank and with thosea'headof it. Thus is continuously and progressively established, for subsequent seam and/or seal glue imprinting purposes, as hereinafter described, the shallowly shingled or overlapped blank assembly shown generally atE in Fig. 1.

This blank assembly E, regardless of the exact shape or outline of its constituent partly-folded blanks, has these: outstanding characteristics, viz., (1) it exposes right next. to each: other the two different glue receiving areas of. any two adjacent blanks thereof, so that a single glue imprinting station (see 52) past which said shingled assembly is moved can serve for seal glue imprinting as well as for seam glue imprinting, and (2) its speed of advance, as established by the above described overtakchines.

ing operation, is very appreciably lower, in every case, than the highest speed of blank movement through the machine, thi'slast being the speed at which the successive spaced apart blanks undergo initially, as above described, the infolding of their side flaps 2, 2, and subsequently, as hereinafter described, the folding over of their respective back or bottom flaps 3, into adhesive seam connection with their side flaps.

Because of this much reduced speed at which the shallowly shingled blank assembly E is advanced past gumming station 52, the latters glue imprinting device or devices, which rotate in step with said assembly, will not attain a speed at which any centrifugal throw off of glue takes place, until the. abovementioned highest blank speed (which. establishes the. envelope production rate of the machine) is two or three times greater than the maximum speed of blank movement (250 to 350 blanks per minme) through conventional rotary envelope making ma- And even if the instant machines production rate is: so drastically increased as to cause some centrifug a-l throw-off of glue from the relatively slow rotating glue imprinting device or devices at station 52, still such thrown-ofi glue particles cannot collect on any of the nearby machine surfaces along which the successive blanks are moving, so as. to foul up the machines operation and necessitate its. stoppage. This is because such machine surfaces, instead of being exposed, as in all conventional rotary machines, by the spacing between successive blanks when the latter are being imprinted with glue, are in this instance. covered at all times by the shingled or overlapped blank assembly E, whose constituent blanks, without any harmful effect, can receive and carry off the small amounts of glue spray or mist thus thrown off.

By virtue of the several factorsabove set forth, a machine in accordance. with the .present invention can achieve production rates as high as 800 to 1000 envelopes per minute, from practically all types of triangular flap envelope blanks. If such triangular flap blanks are of substantially rhombic (including substantially square) shape, as herein shown (with seal flap edges of the same angularity as lower edges of their infolded side flaps), the above described overtaking or shallow shingling openation (which creates the blank assembly E) is availed of to establish, for a purpose hereinafter appearing, a very slight overlap (see 36, 36 Fig. of the lea-ding edges 34, 34 of each following blanks infolded side flaps, by the seal flap edge 35 of the preceding blank of said shingled assembly E. The creation of these overlaps 36, 36 involves another possibility of collision between the underneath fast moving blank and the overlying slow moving blank, which occurs when leading edges 34, 34 of the formers infolded side flaps 2, 2 have been moved up, in each overtaking operation, into close proximity to the trailing slow moving seal flap edges 35, 35 of the preceding blank, as indicated at D in Figs. 1 and 2. To avoid any collision between such edges 34, 34 and 35, 35, and to insure unobstructed passage of the former beneath the latter, the upper high speed shaft 18 carries at its central portion a collar 40, having radially projecting therefrom a forwardly curved spur or book 41. The latters angular position is such that in being moved forwardly and upwardly by the high speed clockwise rotation of shaft 18, said hook will overtake from below the trailing seal flap apex 37 of the preceding slow moving blank, and will temporarily cur-l said seal flap upwardly against a pair of spaced disks 42, 42 on the slow speed shaft 26. During such momentary upward de flection, the side flap edges 34, 34 of the fast moving blank move forward, so that they are always covered by the edges 35, 35 of the preceding blanks seal flap, upon release of the latter by the spur 41.

During the above described progressive shallow shingling of the successive partly-folded blanks B, the latters central portions and extended bottom and seal flaps 3 and 4 are supported against undue downward sagging by a pair of horizontal longitudinally extending rails 43, 43 which, as shown, are spaced sufiiciently far apart so as to permit a blank thereon to undergo centrally a momentary slight downward deflection, when contacted from above by the rotating hook or spur 41. The infolded side flaps of each fast moving blank B, prior to the above described placement of their proximate edges beneath the preceding blanks seal flap edge, may be held down, against any lifting tendency due to air currents or the like, by pairs of overlying plates 44, 44- and 45, 45. The plates 44, 44 are here shown as supported from a cross bar 46 extending between the side frame members 9, 9. The plates 45, 45 which stabilize said infolded side flaps just before their edges 34, 34 pass under the trailing seal flap of the preceding slow moving blank, may be carried, as here shown, by suitable rods 47, 47 extending inwardly from each side frame 9. Before, during and after the shallow shingling operation performed, as above described, on the partlyfolded blanks B, the latter are kept in their horizonta path of travel (line Y, Y, Fig. 3) by underlying skids 48, 48 and by a series of overlying plates or guides 49, 49. The skids 48, 48 are supported adjacent to the respective pairs of rolls 16, 17 and 24, 25 upon cross bars 59, 50 extending between the side frames 9, 9 and the overlying plates 49, 49 are supported adjacently above the blanks by means of rods 51, 51 extending inwardly from the side frames 9, 9.

These and other suitable constraints against any undue blank deflection, up or down, are operative both ahead of and beyond the mechanisms single gumming station, designated generally by the numeral 52, and through which the blanks in shallow shingled assembly (see Fig. 5 and E of Fig. l) are propelled, at the reduced rate of speed established by the pairs of rolls 24, 25. For so slowly feeding the blanks in shingled assembly to and through the gumming station 52, the mechanism provides pairs of upper and lower reed rolls 53, 54, here shown as engaging. with the side edge folds 8, 8 of the shingled blanks. The respective shafts 55 and 56 of rolls 53 and 54 are suitably journalled in the side frame members 9, 9 and carry intermeshing gears 57 and 58 respectively. Gear 58, as shown in Fig. 2, is a double gear, having its other portion in mesh with an idler gear 59 (Figs. 3 and 4) which is driven from the gear 29 of low speed shaft 27. The shaft 56 thus rotates counterclockwise at the same reduced speed as shaft 27, and the gearing is proportioned to give both rolls 53, 54 the same relatively low peripheral or surface speeds as the rolls 24, 25, so as to preserve and keep intact the precise shingled relationship (viz., the successive overlaps 36, 36) which, for the illustrated case of substantially rhombic blanks, is established progressively as above described by conjoint action of fast rolls 16, 17 and slow rolls 24, 25.

At the gumming station 52, each successive zone or region of overlap 36, 36 of the slow speed shingled blank assembly receives a single adhesive imprint, in over-gumming relation to each passing seal flap margin; thus each such imprint is common, as shown at F, Fig. 1, to both of the blanks involved in the overlap. That is to say, each single glue imprint F covers a shaped or contoured marginal area (see stippling 60, Fig. 5) of a preceding blanks seal fiap, plus immediately adjacent narrow areas (stippling 61, 61, Fig. 5) which on the following blanks infolded side flaps, lie just rearwardly of the latters then-overlapped edges 34, 34. For so overgurnming each seal flap of the slow moving shingled blank assembly, the gumming station 52 provides conventional over-gumming means, in the form of an upper roller 62, having a raised and preferably contoured glue imprinting surface 7%, Fig. 6, slightly wider than the desired area 60 of seal flap gluing, and a cooperating platen roller 63. Said parts are carried by upper and lower shafts 64 and 65, which are suitably journalled in the side frame members 9, 9, and carry intermeshing gears 66 and 67 respectively. Lower shaft is rotated in the desired counterclockwise direction by drive of its small diameter gear 67 from an idler gear 68 (Figs. 3 and 4) which is in mesh with the larger gear 58 on slow speed shaft 56. As best shown in Fig. 6, the upper shaft 64, beyond the ends of member 62 carries narrow rolls 69, 69 of the same diameter as the surface of revolution generated by said members contoured segmental glue imprinting surface 79. Said surface of revolution, and the elements 63 and 69 as well, has a circumferential length which is the same as the spacing apart of the seal flap margins, in the shingled blank assembly E.

By the above-described gearing, the shafts 64 and 65 are rotated faster than shaft 56, so as to give the small diameter blank engaging portions 70, 63 and 69 of shafts 64 and 65 the same relatively slow peripheral or surface speeds as the previous rolls 24, 25 and 53, 54. It will thus be seen that rolls 69, 69, by engagement with the side edge folds S, 8 of each blank, cooperate with the underlying platen roller 63 in continuing the leftward travel of the shingled blank assembly E through the gumming station 52 at the same reduced rate of speed imparted thereto by the previous rolls 24, 25 and 53, 54.

At gumming station 52, the contoured segmental glue imprinting surface 70 moves through a circumferential path whose length is the distance apart in the shingled blank assembly E of the successive seal flap margins of its constituent overlapped blanks. At each rotation of shaft 64, the shaped arcuate surface 76 is coated with wet glue in the usual manner from its contact with a suitably rotated overhead glue roll 71 mounted in a glue tub 72, and the timing is such that said surface 70 then makes rolling contact with a seal flap margin of the advancing shingled blank assembly, to deposit along said margin the desired shaped or contoured glue imann l:

by virtue of the extra. or. overgummingZ width: of surface 70, extends in every case. (see. P, Fig. 1.): beyond.

the extreme. edge of each blanks seal fiap: margin and onto. the next blanks infolded; side flaps. 2, 2, to give the. latter, just inwardly of their then-overlapped leading edges 34, 34, the narrow glue imprints 61, 612

Thus. the. extrawide applicator surface 7 0, obtains a full gumming to. the extreme edge of each blanks seal flap; but always deposits its excess glue (totally wasted. and needing to be washed olffin. all. previous. overgumming practice) in seam-sticking. position on pocket-forming flaps of the next blank, the latter thus. servingalways, in effect, as an anti-smut sheet, toprevent any. fouling. of platen roller 63. It is particularly to be. noted that thesesuccessive duplex gumming operations. at station 52 are performed on blanks which are traveling, as. heretofore described; at a. relatively slow speed which is approximately only half the speed at. which the. spaced. blanks are traveling when entering, the present mechanism, and also when leaving. same, as hereinafter described, asspaced apart glued. and folded envelopes- In consequence, there is ample. leewayin mymechanism for these blank entering and envelope exit speeds to be materially and'even drastically stepped-up to give an extremely high rate of envelope production, without encountering at gumming station 52 the centrifugal glue throw-off that sharply limits the envelope production rate of" all prior rotary envelope-making machines, because of need for the latters revolving glue-imprinting devices to have peripheral speeds correspondingto the maximum speed of blank travel throughsuch machines.

In my mechanism, no such production bottleneck is present, because of. the relatively-low peripheral speeds. which. the'revolving glue-imprinting segment 70 needsto attain, in order to keep pace with the slow speedof travel of the shingled blank assembly E; by the same token, there is no such rapid rotation of glue roll 71 as mightproduce undue churning or aeration of the glue supply in tub 72. Moreover, even with my machines envelope production rate stepped-up so drastically as to cause a certain amount of centrifugal glue throw-otffrom imprinting surface 70', there is still no opportunity for suchglue to accumulate on and foul up the variousnearby surfaces alongwhich the blanks are moved, such as the rails 43, the skids 48,

and also a table 73, supported on posts 74, just" beyond the gumming station 52. This isbecause' such surfaces, instead of being exposed as in prior rotary machines by spaces between the advancing blanks, are covered at all times by the shingled assembly E whosesuccessive blanks receive and carry off, without detriment thereto, any such minute glue particles.

For maintaining the shallow shingled relation of the gum-imprinted blanks as they pass from gumming station 52 onto table 73, my invention provides another slow speed forwarding means, here-shownas cooperating pairs' of narrow upper and lower'r0lls-75 and 76,- for engaging. the blanks sideedge folds 8, 8" beyond the endsof the glue imprints 60 and 61, 61 thereon and beyondthe side edges of table 73. Said rolls 75 and 76 have the'same low peripheral or surface speeds as therolls 24, 25, 53,

54, and 69, 63 and are carried by upper and lower shafts- 77 and 78 which are suitably journalled in'the side frames 9, 9, and carry intermeshing gears-79and- 80 respectively. Shaft 73 whose rolls 76, 76 are of the same small diameter as the platen roll 63' is rotated in the desired counterclockwise direction. at the same speed asshaft 65" by drive of its gear 80 from an idler gear 81, which is inmesh with.

rolls-75,. 76, substantially at: the instant that said blanhs 3 of suction; suchas avacuum pump; not shown;

side edge. folds; 8, 8 are seized by the next-encountered;

blankv forwarding rolls which operate, as hereinafter described, at. high peripheral-.orsurface speeds, corresponding substantially tothose of the. initial blank forwarding rolls 19-, 11 and 16, 17', so as: to'obtain delivery from the mechanism, of glued and folded. blanks at the same rapid rate as. said blanks are'fed thereto.

For so speeding up, one after another, the successive glue-imprinted blanks, and restoring their initial spaced relation, the mechanism provides at the forward end of table 73, a large diameter lower roller 83, and for cooperation. therewith a pair of large diameter upper spaced apart narrow roll segments 84, 84. The latters peripheries are: relieved, except for matching bit portions of approximately 90 extent, whose forward. edges at each revolution engage an arriving blank along its side edge folds 8, 8, beyond the freshly gummed areas 60. and 61, 61- thereofl. Thelower roller 83 is journalled for rotation on anormally stationary shaft 85, here shown as hollow for a purpose to be hereinafter described; shaft 85 extends transversely of and beyond the side frame members 9 9. The upper. roll segments 84, 84 are carried by a shaft 86, suitably journalled in said side frames. The shaft 86' and roller 83 carry intermeshing gears 37 and 88 respectively. The lower shaft 78' of the last low speed rolls 7'5, 76, carries, in addition to its small gear 80, a large diameter. gear 89 which, through an idler gear 90 in mesh. with gear 88 on roller 83, drives the roller 83 counterclockwise, and imparts thereto and to roll segments 84', 84 a peripheral or surface speed which is substantially double that. of the roll elements 24, 2'5, 53, 54, 62", 63, and 75, 76 of the slow speed section of the machine.

The high speed blank. forwarding means 83, 84, 84 is so timed and" spaced with relation to the previous slower rolls 75, '76'that each blanks side edge folds 8, 8 are released by one'set of reliefs 82, 82' of rolls 75 just as the forward ends of said side. edge folds are seized by roller 83and' roll'segments 84, 84. The result is to speed up the so' released' blank, and to draw it away, progressively, from the slower moving shingled blank assembly E; at B in Fig. 5 is shown a speeded-up completely glued blank in process of being separated (see G, Fig. 1) from the partly-glued blank just behind it in the slow speed section-of" the machine. Completion. of such separation enables each blank, upon folding over of its bottom flap 3 corporated in the high speed delivery devices 83, 84, 84.

For this purpose, the roll segments 84, 34 at the forward or leading edges of their bite portions, carry between them a transverse scoring blade 91, which is adapted at each revolution, to register with and thrust against a yieldable insert 92, of rubber or the like, extending,

lengthwise of the surface of the underlying roller 83. By such means, each blank, substantially at the instant of its seizure. by high speed-forwarding means 83, 84, 84', is giventhescore line- 93, definitive of the desired fold of itsleadingbottom flap 3-, the latter, previous to such seizureand scoring, having been pushed between and beyond the then-inoperative parts 83, 84, 84 by the action of-final low speed forwardingrolls 75, 76.

Just back of its score line 93, each blank is suctionally gripped by the roller 83, the latter'for this-purpose having lengthwise thereof, behind the yieldable insert 92,, the slit or slits 94' whose inner ends communicate periodically, through a port. or opening 95, with the interior of shaft 85. Said shaft interior is connected to any suitable source The blank B shown in Fig. 5 has been thus suctionally gripped, just behind its score line 93, and drawn downwardly, by rotation of roller 83, toward the line of bite between said roller 83 and an adjacent pressing roller 104; reflecting this partial downward bending of blank B its side edge folds 8, 8 appear as slightly foreshortened, compared to those of the other unbent blanks of Fig. 5. To adjust the angular position of port 95, for close and accurate timing of the seizure and release of successive blanks by roller 83, the hollow shaft 85 carries a worm wheel 96 with which meshes a worm 97 on a vertical shaft 98. The latter provides a handle 99 by which it may be turned to obtain, during operation of the machine, any necessary angular adjustment of the shaft 35, following which the shaft 98 may be locked against turning movement by a locking screw 100.

The pressing roller 104, as hereinafter described, has clockwise rotation (see Fig. 4). Collision between said rollers upper portion and each arriving blanks oppositely moving bottom flap 3 is prevented by a guard member 112, overlying said roller, and attached to a bracket 113 on one side frame 9. In addition, each arriving bottom flap 3 may be deflected upwardly by a projection 101 on roller 83, said projection in the rotation of roller 83 passing through a notch 102 formed in the forward edge of table 73. The above described downward bending of each blank body 1 about the roller 83 tends to throw said blanks trailing seal flap 4 upwardly toward the shaft 86; in order to keep the seal flap glue 60 from making contact with said shaft 86, the latter carries a curved guard 103 adapted to engage each seal flap 4 inwardly of its marginal glue 60.

Each blanks downward movement by roller 33 carries it, score line 93 foremost, into the line of bite between roller 83 and the pressing roller 104, whereupon the suctional grip of roller 83 on said blank is released. The pressing roller 104 is carried on a shaft 105 which is suitably journalled in the side frame members 9, 9 and which carries a gear 106 in mesh with the gear 88 of roller 83. The action of rollers 83 and 104 converts each score line 93 into a definite fold 108, Fig. 1, for the bottom of each envelopes pocket. The effective contact surface of roller 104 has a substantially triangular terminal portion, as shown at 107 in Fig. 2, which corresponds to and registers with each blanks bottom flap 3, the latter being thereby pressed at its edges against the wet glue imprints 61, 61, to complete each envelopes adhesive seam, as shown at 109 in Fig. 1.

The pressing roller 104 at its ends has narrow circular blank forwarding portions 120, 120, substantially flush with the triangular portion 107, but elsewhere said rollers periphery is suitably relieved, to avoid any contact therewith of the wet glue 60 on each successive envelopes trailing seal flap 4. A further safeguard against such contact is provided by said rollers projection 110 (see Fig. 4) which is so located as to keep each passing seal flap 4 from swinging toward the roller 104, and which in the joint rotation of rollers 83 and 104, is received at each revolution in the formers relieved portion 111, Fig. 4.

Each seamed envelope, in the condition shown at H, Fig. 1, has its rapid movement continued by the bite on its side edges 8, 8, of roller 83 and the end portions 120, 120 of roller 104. A suitable stripper 114, Fig. 4, is so positioned as to guide or defiect each such envelope, advancing bottom fold 108 foremost, into the narrow lines of bite between said roller portions 120, 120 and an underlying pair of disks 115, 115, which are mounted on a shaft 116 that carries a gear 117 in mesh with the gear 106 of shaft 105. A travelling belt 118, against which the envelope edge portions 8, 8 are pressed by suitable overlying narrow rollers 11), may then be employed to receive the envelopes and deliver them in rapid succession to the fingers of a travelling dryer chain, not shown.

The described mechanism is readily adaptable to the production of envelopes of different sizes, merely by ad-. justing, toward or away from center line 4-4 of Fig. 2, the positions of the several sets of forwarding rollers 16, 17, 24, 25, 53, 54, 75, 76, etc., on their respective shafts. For such changes in envelope size, the only parts requiring replacement are the glue applying roller 62 and the roller 104.

From the foregoing, it is clear that my invention, in its illustrated preferred embodiment, when operating on wholly symmetrical diamond-shaped blanks, such as shown by the drawings herein, will convert such blanks, at speeds of production never before achieved, into envelopes of the highest quality. In all such envelopes the contoured seal flap gumming extends uniformly to the flaps extreme edge, by virtue of the described novel procedures and devices which obtain overgumming of each blanks seal flap, in the entire absence of the usual glue wastage, and of the usual complications attendant upon washing off of the excess glue.

But my invention is not limited, except as specified in the appended claims, to operation on blanks of wholly symmetrical diamond shape, nor to the achievement always of the described perfection of the seal flap gluing. For it is clear that the principles of my invention, insofar as they overcome or mitigate the production bottlenecks of all prior rotary envelope-making machines and methods, are of general application, and are extremely useful in achieving greatly increased speeds of envelope production from blanks of other than the herein illustrated symmetrical diamond shape. For such purposes, it is merely required, as described above, that the illustrated glue applying and folding rollers 62 and 104 respectively be replaced by roller elements of appropriate form and shape to meet the glue applying and back flap folding needs of the particular shapes of blanks being operated upon. 1

I claim:

1. In envelope making mechanism, means for folding over the side flaps of successive substantially rhombic blanks advancing flatwise in spaced relation, means for overtaking each so-folded blank by the next-following sofolded blank but only to an extent such that lower edges of the folded-over side flaps of the one are slightly overlapped by the seal fiap edge of the other, and means for thereafter separately applying to each seal flap of the sooverlapper blanks a marginal adhesive imprint, in overgumming relation to said seal flaps edge, whereby the ex cess adhesive of each application is received on the adjacent blanks folded-over side flaps, for subsequent sticking thereto of said blanks bottom flap.

2. In envelope making mechanism, means for folding over the side flaps of successive substantially rhornbic blanks advancing flatwise in spaced relation, with their seal flaps trailing, means for overtaking each sofolded blank by the one next following but only to an extent such that leading edges of the latters folded-over side flaps are slightly overlapped by the formers trailing seal flap edge, and means for thereafter separately applying to each seal flap of the so-overlapped blanks a marginal contoured adhesive imprint, in over-gumming relation to said seal fiaps edge, whereby the excess adhesive of each application is received on the following blanks folded-over side flaps for subsequent sticking thereto of said follow-ing blanks bottom flap.

3. In envelope making mechanism, means for folding over the side flaps of successive substantially rhombic blanks advancing flatwise in spaced relation, means for overtaking each so-folded blank by the next-following so-folded blank but only to an extent such that lower edges of the folded-over side flaps of the one are slightly overlapped by the seal flap edge of the other, means, operative during each overtaking action for preventing collisions between the flaps of the respecttive overtaking and overtaken blanks, and means for separately applying to each seal flap of the so-overlapped blanks a marginal imprint of contoured gumming, in over-gumming relation to said seal flaps edge, whereby the excess gum of each application is received on the following blanks folded-over side flaps for subsequent sticking thereto of said following blanks bottom flap.

4. In envelope making mechanism, means for folding over the side flaps of successive substantially rhombic blanks advancing fiatwise in spaced relation, with their seal flaps trailing, means for overtaking each so-folded blank by the one next following but only to an extent such that leading edges of the latte-rs folded-over side flaps are slightly overlapped by the formers trailing seal flap edge, means operative at the start of each overtaking action to deflect upwardly the trailing seal flap of the preceding blank, for entry beneath same of the following blanks leading bottom flap, and means for separately applying to each seal flap of the so-overl'apped blanks a marginal imprint of contoured gumming, in over-gumming relation to said seal flaps edge, whereby the excess gum of each application is received on the following blanks foldedover side flaps for subsequent sticking thereto of said following blanks bottom flap.

5. In envelope making mechanism, means for folding over the side flaps of successive substantially rhombic blanks advancing fiatwise in spaced relation, with their seal flaps trailing, means for overtaking each so-folded blank by the one next following but only to an extent such that leading edges of the latters folded-over side flaps are slightly overlapped by the formers trailing seal fl-ap edge, means operative near the finish of each overtaking action to deflect upwardly the trailing seal flap of the preceding blank, for entry beneath same of leading edges of the following blanks folded-over side flaps, and means for separately applying to each seal flap of the so-overlapped blanks a marginal imprint of con-toured gumming, in over-gumming relation to said seal fiaps edge, whereby the excess gum of each application is received on the following blanks folded-over side flaps for subsequent sticking thereto of said following blanks bottom flap. I

6. In envelope making mechanism, means for folding over the side flaps of successive substantially rhombic blanks "advancing fiatwise in spaced relation, with their seal flaps trailing, means for overtakingeach so-folded blank by the one next following but only to an extent such that leading edges of the latters folded-over side flaps are slightly overlapped by the formers trailing seal flap edge, means operative at the start of each overtaking action to deflect upwardly the trailing seal flap edge of the preceding blank, for entry beneath same of the following blanks leading bottom flap, means operative near the finish of each overtaking action to deflect upwardly the trailing seal flap edge of the preceding blank for entry beneath same of leading edges of the following blanks folded-over side flaps, and means for separately applying to each seal flap of the so-over-lapped blanks a marginal imprint of contoured gumming, in over-gumming relation to said seal fia-ps edge, whereby the excess gum of each application is received on the following blanks folded-over side flaps for subsequent sticking thereto of said following blanks bottom flap.

7. In envelope making mechanism, means for fol-ding over the side flaps of successive substantially rhombic blanks advancing fiatwise in spaced relation, means for progressively changing the spaced relation of the advancing partly-folded blanks to a relatively shallow shingled or stepped relation, wherein each blanks seal flap slightly overlaps the bottom edges of an adjacent blanks foldedover side flaps, a glue applying station through which the blanks, in said shingled assembly are advanced, and means at said station, rotating in timed relation to said assemblys advance for applying separately, to each seal flap margin of said assembly a contoured area of gumming, in overgumming relation to the edge of said seal fiap, whereby the excess gum of each application is received on the adjacent blanks folded-over side flaps for subsequent stickin-g thereto of its bottom flap.

8. In envelope making mechanism, means for folding over the side flaps of successive substantially rhombic blanks advancing fiatwise in spaced relation, means for progressively changing the spaced relation of the advancing partly-folded blanks to a relatively shallow sh-ingled or stepped relation, wherein each blanks seal flap slightly overlaps the bottom edges of an adjacent blanks foldedover side flaps, a glue applying station through which the blanks, in said shingled assembly are advanced, means at said station, rotating in timed relation to said assemblys advance, for applying separately, to each seal flap margin of said assembly a contoured area of gumming, in overgummin-g relation to the edge of said seal flap, whereby the excess gum of each application is received near the bottom edges of the adjacent blanks folded-over side flaps, means beyond said station for withdrawing successively from said assembly the leading blank thereof, and means for thereafter folding over each withdrawn blanks bottom flap into seam-forming contact with the adhesive received on its folded-over side flaps.

9. In envelope making mechanism, means for folding over the side flaps of successive substantially rhombic blanks advancing fiatwise in spaced relation at relatively high speed, means for reducing each so-folded blanks speed, after a predetermined movement of same at said high speed, to obtain such overtaking of same by the next-following so-folded blank as to dispose bottom edges of one blanks folded over side flaps beneath the seal flap edge of the other blank, means for advancing the successive so-overlapped blanks at said reduced speed, and means in the region of said reduced speed advance for applying separately to each seal flap margin a contoured area of gumming, in over-gumming relation to said seal flaps edge, whereby the excess gum of each application is received on the following blanks infolded side flaps for subsequent sticking thereto of said blanks bottom flap.

10. In envelope making mechanism, means for folding over the side flaps of successive substantially rhombic blanks advancing fiatwise in spaced relation at relatively high speed, means for reducing each so-fol'ded blanks speed, after a predetermined movement of same at said high speed, to obtain such overtaking of same by the next-following so-folded blank as to dispose bottom edges of one blanks folded over side flaps beneath the seal flap edge of the other blank, means for advancing the successive so-overlapped blanks at said reduced speed, means in the region of said reduced speed advance for applying separately to each seal flap margin a contoured area of gumming, in over-gumming relation to said seal flaps edge, whereby the excess gum of each application is received near the bottom edges of the following blanks folded-over side flaps, means operative on each blank after the gumming of its seal flap to increase its speed of advance, thereby to withdraw it from the nextfollowing blank, and means for thereafter folding over such withdrawn blanks bottom flap into seam-forming contact with the adhesive received on its folded-over side flaps.

11. In envelope manufacture, for the application of seal flap adhesive and seam-sticking adhesive to a succession of substantially rhombic blanks, the improvement which consists in folding inwardly each blanks side flaps while they are advancing fiatwise in spaced relation, progressively changing the spaced relation of the advancing partly folded blanks to a shallowly shingled or stepped relation, wherein each blanks seal flap slightly overlaps the bottom edges of an adjacent blanks infolded side flaps, preventing during such change any collisions between the flaps of the respective blanks, and producing at each zone of said slight flap overlap of the advancing so-shingled blanks a single adhesive imprint, common to both blanks, whereby one has its seal flap gummed fully to the edge and the other receives av'aeii l adhesive for subsequent sticking of its bottom flap to its infolded side flaps.

12. In envelope manufacture, for the application of seal flap adhesive and seam-sticking adhesive to a succession of substantially rhombic blanks advancing flatwise in spaced relation, with their seal flap portions trailing, the improvement which consists in folding inwardly each blanks side flaps, progressively changing the spaced relation of the advancing partly folded blanks to a shallowly shingled or stepped relation, wherein each blanks seal flap slightly overlaps the bottom edges of the next blanks infolded side flaps, preventing during such change any collisions between the flaps of the respective blanks, and producing at each zone of said slight flap overlap of the advancing sol-shingled blanks a single adhesive imprint, common to both blanks, whereby one has its seal flap gummed fully to the edge and the other receives adhesive for subsequent sticking of. its bottom flap to its infolded side flaps.

13. In the manufacture of envelopes from a succession of substantially rhombic blanks advancing flatwise in spaced relation, the improvement which consists in folding inwardly the side flaps of each blank, progressively assembling the party-folded blanks in a shallowly shingled or stepped relation, wherein each blanks seal flap slightly overlaps the bottom edges of an adjacent blanks infolded side flaps, preventing during such assembly any collisions between the flaps of the respective blanks, causing the so-shingled blank assembly to receive at each zone of said slight flap overlap a single adhesive imprint common to the two blanks thereof, whereby one blanks seal fiap is gummed to its extreme edge and the other blanks infolded side flaps receive seam-sticking adhesive, and progressively disassembling the so-gumrned blanks and restoring their spaced relation to permit each blanks bottom flap to be folded into pocket-forming engage ment with the adhesive on its infolded side flaps.

14. In the manufacture of envelopes from a succession of substantially rhombic blanks advancing fiatwise in spaced relation, with their seal flap portions trailing, the improvement which consists in folding inwardly the side flaps of each blank, progressively assembling the partlyfolded blanks in a shallowly shingled or stepped relation, wherein each preceding blanks trailing seal flap slightly overlaps the bottom edges of the next blanks infolded side flaps, preventing during such assembly any collisions between the flaps of the respective blanks, causing the so-shingled blank assembly to receive at each zone of said slight flap overlap a single adhesive imprint common to the two blanks thereof, whereby the preceding blanks seal flap is gurnmed to its extreme edge and the following blanks infolded side flaps receive seam-sticking adhesive, and progressively disassembling the so gummed blanks and restoring their spaced relation to permit each blanks bottom fiap to be folded into pocketforming engagement with the adhesive on its infolded side flaps.

15. In the manufacture of envelopes, from a succession of substantially rhombic blanks advancing fiatwise, bottom flaps foremost, in spaced relation, the improvement which consists in successively folding inwardly each blanks side flaps, progressively assembling the advancing partly-folded blanks in a shallowly shingled or stepped relation, to slightly overlap each blanks trailing seal flap upon the bottom edges of the following blanks infolded side flaps, preventing during such assembly any collision between the flaps of the res ective blanks, producing at each zone of said slight flap overlap of said assembly a single adhesive imprint common to the two blanks thereof, to supply one blank with seal flap adhesive and the other with seam-sticking adhesive, progressively restoring the spaced relation of the so-gnmrned blanks, and causing each blanks bottom flap to be folded into seam-forming relation with said last-mentioned portion of said common adhesive imprint.

16. In the manufacture of envelopes, for application of seal flap adhesive and seam-sticking adhesive to the blanks thereof, the improvement which consists in folding over the side flaps of successive advancing spaced apart blanks having seal flap edges of substantially the same angularity as the lower edges of their folded over side flaps progressively overtaking each partly-folded blank by the one next following, to an extent that slightly overlaps the seal flap edge of one upon lower edges of the others infolded side flaps, and depositing at each such zone of said slight flap overlap of the advancing blanks a single adhesive imprint common to both blanks of said zone, whereby one blank has its seal flap gummed to the extreme edge and the other receives adhesive for sticking the seams of its side and bottom flaps.

17. In the manufacture of envelopes, for application of seal flap adhesive and seam-sticking adhesive to the blanks thereof, the improvement which consists in folding over the side flaps of successive advancing spaced apart blanks having seal flap edges of substantially the same angularity as the lower edges of their folded over side flaps progressively shingling the so-folded blanks to a depth such that each blanks seal flap edge slightly overlaps the lower edges of the adjacent blanks folded over side flaps, and moving the blanks in such shingled assembly past a single rotary adhesive imprinting device, to receive therefrom successive spaced adhesive imprints at and common to said overlapped edge portions of adjacent blanks.

18. In envelope making mechanism, means for folding over the side flaps of a succession of substantially rhombic blanks, means for progressively shingling the so-folded blanks but only to a depth such that each blanks seal flap edge slightly overlaps the lower edges of the adjacent blanks folded-over side flaps, means for applying successive spaced imprints of glue to said shingled assembly in regions at and common to said slightly overlapped edge portions of adjacent blanks thereof, means for progressively de-shingling the so-glued blanks, and means operative thereafter on each blank to fold over its bottom flap against the glue on the marginal portions of its folded over side flaps.

19. In the manufacture of envelopes, for application of seal flap adhesive and seam-sticking adhesive to the blanks thereof, the improvement which consists in folding in the side flaps of a succession of advancing spaced apart blanks having seal flap edges substantially parallel to lower edges of their infolded side flaps, assembling the so-folded blanks progressively in a shallow shingled rela tion such that lower edges of each blanks infolded side flaps are slightly overlapped by the seal flap edge of the adjacent blank, and overgumming each of the successive seal flaps of said shingled blank assembly, whereby the excess gum of each overgumming operation is received on narrow areas near said lower edges of the adjacent blanks infolded side flaps, for adhering said blanks bottom flap thereto.

20. In envelope making mechanism, means for folding over the side flaps of a succession of substantially rhombic blanks, means for progressively assembling the so-folded blanks in a shingled relation of only such depth that each blanks seal flap slightly overlaps the lower edges of the adjacent blanks folded over side flaps, and rotary glue imprinting means operating in timed relation to the movement past same of said shingled assembly for imprinting thereon successive contoured adhesive areas, each in over-gumming relation to the margin of the respective seal flaps of said assemblys constituent blanks, whereby to deposit the excess gum at each operation thereof, on narrow areas near the lower overlapped edges of the adjacent blanks folded over side flaps, for subsequent adhesion thereto of said blanks bottom fiap.

21. The improvement in the manufacture of envelopes which consists in advancing in spaced relation a succession of substantially rhombic envelope blanks each with its side flaps folded over upon the blank body and with its bottom and seal flaps extended, assembling said blanks in a shallowly shingled relation with the seal flap of each blank disposed over the bottom flap of an adjacent blank so that the edge of the seal flap just overlaps the bottom edge portions of the folded over side flaps of the adjacent blank, and successively applying to the seal flap of each blank while the blanks are so shingled a swath of gum of sufficient width so as to gum the margin of the seal flap and be received on the folded over side flaps of the adjacent blank so as to provide gummed areas on each blank for adhesively securing its bottom and seal flaps to the envelope body.

22. The improvement in the manufacture of envelopes which consists in advancing in spaced relation a succession of substnatially rhornbic envelope blanks each with its side flaps folded over upon the blank body and vwith its bottom and seal flaps extended, assembling said blanks in a shallowly shingled relation with the seal flap of each blank disposed over the bottom flap of an adjacent blank far enough for the edge of the seal flap to just overlap the bottom edge portions of the folded over side flaps of the adjacent blank, successively applying to the seal flap of each blank while the blanks are so shingled a swath of gum of sufficient width so as to gum the margin of the seal flap and be received on the folded over side flaps of the adjacent blank, separating the shingled blanks, and then folding each bottom flap over its envelope body so that its marginal portion will be disposed upon the gummed portion of its associated side flaps.

23. The improvement in the manufacture of envelopes which comprises advancing in spaced relation a succession of substantially rhombic envelope blanks bottom flap foremost and in a direction parallel to the side flap folds, each envelope blank having its side flaps folded over upon the blank body and its bottom and seal flaps extended, while so conveying the blanks assembling them in a shallowly shingled relation with the seal flap of each blank disposed over the bottom flap of an adjacent blank so that the edge of the seal flap just overlaps the bottom edge portions of the folded over side flaps of the adjacent blank, and successively applying to the seal flap of each blank while the blanks continue to move in a forward direction and in a shingled relation, a swath of gum of sufiicient width so as to gum the margin of the seal flap and be received on the bottom portions of the folded over side flaps of the adjacent blank thereby to provide two spaced gummed areas on each blank for adhesively securing its bottom and seal flaps to the envelope body.

24. The improvement in the manufacture of envelopes which comprises advancing in spaced relation a succession of substantially rhombic envelope blanks bottom fi'ap foremost and in a direction parallel to the side flap folds, each envelope blank having its side flaps folded over upon the blank body and its bottom and seal flaps extended, while so conveying the blanks assembling them in a shallowly shingled relation with the seal flap of each blank disposed over the bottom flap of an adjacent blank so that the edge of the seal flap just overlaps the bottom edge portions of the folded over side flaps of the adjacent blank, successively applying to the seal flap of each blank, while the blanks continue to move in a forward direction and in a shingled relation, a swath of gum of sufiicient width so as to gum the margin of the seal flap and be'received on the bottom portions of the folded over side flaps of the adjacent blank, separating the shingled blanks during their forward movement, and then successively folding the bottom fiap of each blank over its associated blank body so that its marginal portion will adhere to the gummed area of the folded over side flaps.

25. In the manufacture of envelopes which includes the successive steps of advancing a continuous Web of envelope material, severing said web along successive oblique lines thereby to form separate unconnected envelope blanks each in substantially rhombic form, ad-

'vancing said blanks in spaced relation in a path which diverges fromthe web pat. at an obtuse angle so that each blank will be forward-*l bottom flap foremost and in a direction parallel to a diagonal connecting the apices of the bottom and seal flaps, and successively folding the oppositely disposed side flaps of each blank over its body portion; the combination therewith of the successive steps which include assembling said blanks in a shallowly shingled relation with the seal flap of each blank disposed over the bottom flap of an adjacent blank so that the edge of the seal flap just overlaps the bottom edge portions of the folded over side flaps of the adjacent blank, successively applying to the sealflap of each blank, while the blanks continue to move in a forward direction and in such shingled relation, a swath of gum of sufficient width so as to gum the margin of the seal flap and be received on the bottom portions of the folded over side flaps of the adjacent blank, separating the shingled blanks during their forward movement, and then successively folding the bottom flap of each blank over its associated blank body so that its marginal portion will adhere to the gummed area of the folded 'wise in spaced relation, the improvement which consists in folding inwardly each blanks side flaps, changing'the I spaced relation of the advancing partly folded blanks to a shallowly shingled or stepped relation, wherein each blanks seal flap slightly overlaps the bottom edges of an adjacent blanks infolded side flaps, and producing at each Zone of slight flap overlap of the advancing soshingled blanks a single adhesive imprint, common to both blanks, whereby one has its seal flap gummed fully to the edge and the other receives adhesive for subsequent sticking of its bottom flap to said infolded side flaps.

27. In envelope manufacture, for the application of seal flap adhesive and seam-sticking adhesive to a succession of substantially rhombic blanks advancing'fiatlap of the advancing s-o-s'hingled blanks a single adhesive imprint, common to both blanks, whereby one has its seal flap gummed fully to the edge and the other receives adhesive for subsequent sticking of its bottom flap to said infolded side flaps.

28. In the manufacture of envelopes from a succession of substantially rhombic blanks advancing flatwise in spaced relation, the improvement which consists in folding inwardly the side flaps of each blank, then assembling the partly-folded blanks in a shingled or stepped relation, wherein each blanks seal flap slightly overlaps. the bottom edges of an adjacent blanks infolded side flaps, causing the so-shingled blank assembled to receive at each zone of slight flap overlap a single adhesive imprint common to the two blanks thereof, whereby one blanks seal flap is gummed to'its extreme edge and the other blanks infolded side flaps receive seam-sticking adhesive, and thereafter disassembling said blanks and restoring their spaced relation to permit each blanks bottom flap to be folded into pocket-forming engagement with the adhesive on said infolded side flaps.

29. In the manufacture of envelopes fnom a succession of substantially rhombic blanks advancing fiatwise in spaced relation, with their seal flap portions trailing, the improvementwhich consists in folding inwardly the side flaps of each blank, then assembling the partly-folded blanks in a shingled or stepped relation, wherein each blanks seal flap slightly overlaps the bottom edges :of the next blanks infolded side flaps, causing the so-shingled blank assembly to receive at each zone of slight flap overlap a single adhesive imprint common to the two blanks thereof, whereby one blanks seal flap is gummed to its extreme edge and the other blanks infolded side flaps receive seam-sticking adhesive, and thereafter disassembling said blanks and restoring their spaced relation to permit each blanks bottom flap to be folded into pocket-forming engagement with the adhesive 'on said infolded side flaps.

30. In the manufacture of envelopes, from a succession of substantially rhombic blanks advancingflatwise, bottom flaps foremost, in spaced relation, the improvement which consists in successively folding inwardly each blanks side flaps, progressively assembling the advancing partly-folded blanks in a shingled or stepped relation, to slightly overlap each blanks seal flap edge upon the bottom edges of the following blanks infolded side flaps, producing at each zone of slight flap overlap of said assembly a single adhesive imprint common to the two blanks thereof, to supply one blank with seal flap adhesive and the other with seam sticking adhesive, then restoring the spaced relation of said blanks, and causing each blanks bottom flap to be folded into seam-forming relation with said last-mentioned adhesive.

31. In mechanism for making envelopes from a succession of substantially diamond-shaped blanks, a rotary overgumming adhesive applicator for the seal flap margin-s of said blanks, means for folding inwardly the side flaps of the successive blanks during their advance in spaced relation, means for reducing, at the same point in each blanks movement, its speed of advancement, to establish a shallow shingled relation of only such depth as to overlap the edge of each blanks seal flap upon the proximate edges of an adjacent blanks folded-over side flaps, means for coordinating the rotation of said applicator to the reduced speed movement past same of the so-shingled blanks for the gumming of each seal flap to its extreme edge, and for the deposit of said applicators excessive adhesive upon the adjacent blank, near its overlapped proximate side flap edges, and means for progressively de-shingling said blanks, and folding their respective bottom flaps against the adhesive on their folded-over side flaps.

32. In mechanism for making envelopes from a succession of substantially diamond-shaped blanks, a rotary overgumming adhesive applicator for the seal flap margins of said blanks, means for folding inwardly the side flaps of the successive blanks during their advance in spaced relation, means for reducing, at the same point in each blanks movement, its speed 'of advancement, to establish a shallow shingled relation of only such depth as to overlap the edge of each blanks seal flap upon the proximate edges of an adjacent blanks folded-over side flaps, means for coordinating the rotation of said applicator to the reduced speed movement past same of the soshingled blanks for the gumming of each seal flap to its extreme edge, and for the deposit of said applicators excess adhesive upon the adjacent blank, near its overlapped proximate side fiap edges, means operating on each blank beyond said applicator to space it from the following blanks, and means for thereafter folding the bottom flap of each so-spaced blank against the adhesive on its folded-over side flaps.

'33. In envelope manufacture, for the application of seal flap adhesive and seam-sticking adhesive to a succession of blanks advancing fiatwise in spaced relation, the improvement which consists in folding inwardly each blanks side flaps, changing the spaced relation of the advancing partly folded blanks to a shallowly shingled or stepped relation wherein the seal flap margin of each blank and the proximate seam forming margins of the next blanks infolded side flaps are exposed in juxtaposed relation, and imprinting with adhesive the successive pairs of juxtaposed difierent marginal flap areas of the so- 2t) shingled blank assembly, to provide at each imprinting operation, the seal flap adhesive for one blank and the seam-sticking adhesive for the other.

34. In envelope manufacture, for the application of seal flap adhesive and seam-sticking adhesive to a succession of blanks advancing fiatwise in spaced relation, the improvement which consists in folding inwardly each blanks side flaps, reducing, at the same'point in each blanks movement, its speed of advancement, to establish .a shallowly shingled or stepped relation wherein the seal flap margin of each blank and the proximate seam-forming margins of the next blanks infolded side flaps are exposed in juxtaposed relation, and imprinting with adhesive, during the reduced speed advancement of such so-shingled blank assembly, the successive pairs of sojuxtaposed different marginal flap areas to provide at each imprinting operation, the seal flap adhesive for one blank and the seam-sticking adhesive for the other.

35. In envelope manufacture, for the application of seam-sticking adhesive to a succession of blanks ZICiV-HHG ing fiatwise in spaced relation, the improvement which consists in folding inwardly each blanks side flaps, reducing, at the same point in each partly folded blanks movement, its speed of advance, to establish a shallowly shingled or stepped relation wherein the seal flap margin of each blank and the proximate seam-forming margins of the next blanks infolded side flaps are exposed in Y juxtaposed relation, and imprinting with adhesive, during the reduced speed advancement of such so-shingled blank assembly, each blanks said marginal side flap areas, to provide the seam-sticking adhesive thereof.

36. In envelope manufacture, for the application of shaped or contoured areas of adhesive to the seal flaps of a succession of blanks, advancing fiatwise in spaced relation, the improvement which consists in folding inwardly each blanks side flaps, reducing, at the same point in each partly folded blanks movement, its speed of advancement, to establish a shallowly shingled or stepped relation wherein the seal flap margin of each blank and the proximate seam-forming edges of the next blanks infolded side flaps are exposed in juxtaposed relation, and imprinting with adhesive, during the reduced speed advancement of such so-shingled blank assembly, the successive spaced-apart marginal seal flap areas thereof.

37. In envelope making mechanism, means for advancing a succession of blanks in spaced relation, means for folding inwardly each blanks side flaps, means for reducing at the same point in each so-folded blanks movement its speed of advancement, to establish a stepped or shingled relation wherein each blanks seal flap and the proximate seam-forming edges of the next blanks infolded side flaps are exposed in juxtaposed relation, and a rotary glue imprinting segment having a peripheral speed corresponding to said reduced speed of blank advancement'for imprinting shaped areas of glue upon the vsuccessive seal flap marginal areas of said shingled blank assembly.

38. Intenvelope making mechanism, means for advancing a succession of blanks in spaced relation, means for folding inwardly each blanks side flaps, means for reducing at the same point in eachso-folded blanks movement'its speed of advancement, to establish a stepped :or'shingled relation wherein each blanks seal flap edge and the proximate seam-forming edges of the next blanks infolded side flaps are exposed in juxtaposed relation, and a rotary glue imprinting segment having a peripheral speed corresponding to said reduced speed of blank advanc'ement for imprinting seam-sticking glue on each blank, along the aforesaid seam-forming edges of its infol si e fl ps- 3-9. In envelope making mechanism, means foradvancing a succ s ion of lanks in spaced relation, means for folding inwardly each blanks side flaps, meansffor redu ins at he same point .in each o-folded blank m v ment its speed of advancement, to establish'a stepped gnaw or shingled relation wherein each blanks seal flap and the proximate seam-forming edges of the next blanks infolded side flaps are exposed in juxtaposed relation, and a rotary glue imprinting segment having a perlpheral speed corresponding to said reduced speed of blank a dvancement for imprinting glue on the successive pairs of juxtaposed dilferent marginal flap areas, whereby at each operation thereof to imprint seal flap glue on one blank and seam-sticking glue on the other blank.

40. In mechanism for making envelopes from a succession of blanks advancing in spaced relation at high speed, means for folding inwardly the lateral pocketforming flaps of successive so-advancnrg blanks, means for so slowing down, at the same point in each so-folded blanks movement, its speed of advance, as to create a slow-moving shallowly shingled blank assembly that exposes the seam forming margins of each blanks infolded lateral flaps in close proximity to the ad acent blanks seal flap margin, means for imprinting w th adhesive the successive so-exposed seam forming marglns, means operative on each blank, after such application thereto of adhesive, to restore its high speed advancement and its spaced relation to the next-following blank, and means operative on each blank during its restored h1gh speed advancement for folding inwardly its lower pocket-forming flap into adhesive-seam connection with the imprinted marginal areas of said previously-folded lateral pocketforming flaps.

41. In mechanism for making envelopes from a succession of blanks advancing in spaced relation at high speed, means for folding inwardly the lateral pocketforming flaps of successive so-advancing blanks, means for so slowing down, at the same point in each so-folded blanks movement, its speed of advance, as to create a slow-moving shingled or overlapped blank assembly wherein corresponding marginal areas of each blanks infolded flaps are left uncovered by the adjacent blank of said assembly, means for imprinting with adhesive the successive so-uncovered areas of said slow-moving blank assembly, means operative on each blank, after such application thereto of adhesive, to restore its high speed advancement and its spaced relation to the next-following blank, and means operative on each blank during its restored high speed advancement for folding inwardly its lower pocket-forming flap into adhesive-seam connection with the imprinted marginal areas of said previouslyfolded lateral pocket-forming flaps.

42. In envelope making mechanism, means for advancing a succession of blanks at high speed in spaced relation, with their bottom and lateral pocket-forming flaps extended, means operative on each blank during its said high speed advance to fold inwardly its lateral pocketforming fiaps, means for changing, at the same point in each so-folded blanks movement its speed of advancement, for progressive creation of a shallowly shingled blank assembly wherein marginal areas of each blanks infolded lateral pocket-forming flaps are left exposed in close proximity to the preceding blanks seal flap margin, adhesive imprinting means, rotating in step with said changed speed, for producing adhesive imprints on the successive so-exposed marginal flap areas of the blanks of said assembly, means operative on each foremost blank of said assembly, after such application thereto of adhesive, to restore its high speed advancement and its spaced relation to the next-following blank, and means for then folding inwardly the bottom pocket-forming flap of each blank, into adhesive seam connection with its previously infolded lateral pocket-forming flaps.

43. In the manufacture of envelopes from a succession of blanks advancing in spaced relation at high speed, the improvement which consists in folding inwardly the lat eral pocket-forming flaps of each such blank, so slowing down, at the same point in each so-folded blanks movement, its speed of advance as to create a slow-moving shallowly shingled blank assembly wherein seam-forming 'marginal areas of each blanks infolded lateral flaps are left exposed in close proximity to the preceding blanks seal flap margin, imprinting with adhesive, at the slowed down speed of said blank assembly, the successive soexposed marginal areas of its blanks lateral pocket-forming flaps, restoring to each blank, after such adhesive application, its high speed advancement and its spaced relation to the next-following blank, and folding inwardly, during each blanks restored high speed advancement, its lower pocket-forming flap, to obtain adhesive seam connection thereof with the imprinted marginal areas of its previously-folded lateral pocket-forming flaps.

44. In the manufacture of envelopes from a succession of blanks advancing in spaced relation at high speed, the improvement which consists in folding inwardly the lateral pocket-forming flaps of each such blank, so slowing down, at the same point in each so-folded blanks movement, its speed of advance as to create a slow-moving shingled blank assembly wherein corresponding marginal areas of each blanks infolded lateral flaps and of the adjacent blanks seal flap are exposed in juxtaposed relation, imprinting with adhesive the successive pairs of said soexposed flap areas of the slow-moving blank assembly, restoring to each blank, after such adhesive application, its high speed advancement and its spaced relation to the next-following blank, and folding inwardly, during each blanks restored high speed advancement, its lower pocketforming flap, to obtain adhesive seam connection thereof with the imprinted marginal areas of its previouslyfolded lateral pocket-forming flaps.

45. In the manufacture of envelopes from a succession of blanks advancing at high speed in spaced relation with their bottom and lateral pocket-forming flaps extended, the improvement which consists in folding inwardly during each blanks high speed advance its lateral pocketforming flaps, reducing at the same point in each so-folded blanks movement its speed of advancement, thereby to create with the next-following so-foldecl blank a shallowly shingled or overlapped relation that exposes corresponding marginal areas of each blanks infolded lateral pocketforming flaps in close proximity to the seal flap margin of the preceding blank, imprinting with adhesive, at said reduced speed of the so-shingled blanks, the so-exposed marginal areas of each blanks lateral pocket-forming flaps, restoring to each blank, after such application thereto of adhesive, its high speed advancement and its spaced relation to the next-following blank, and folding inwardly, during each blanks restored high speed advancement, its bottom pocket-forming flap to obtain adhesive seam connection thereof with the adhesive-imprinted margins of its previously-folded lateral pocket-forming flaps.

46. In envelope making mechanism, means for ad vancing a succession of blanks at high speed in spaced relation, means for folding in the side flaps of successive soadvancing blanks, pairs of narrow rolls operative on the opposite side edge folds of each blank to continue its advance, but at such a lower speed, that its overlap with the blank next following exposes in juxtaposed relation the seam-forming margins of one blanks infolded side flaps, and the seal flap margin of the other blank, means for imprinting with adhesive the so-exposed areas of the slow moving overlapped blanks, narrow rolls operative on the side edge folds ofeach blank beyond said adhesive applications to restore its high speed advancement and its spaced relation to the next-following blank, and means operative on each blank during its restored high speed advancement for folding inwardly its lower pocket-forming flap into adhesive seam connection with the margins of its previously-infolded side flaps.

47. In envelope making mechanism, means for advancing a succession of blanks at high speed in spaced relation, means for folding in the side flaps of successive soadvancing blanks, pairs of narrow rolls operative on the opposite side edge folds of each blank to continue its advance, but at such a lower speed that its overlap with the tion to the next-following blank, and means operative on each blank during its restored high speed advancement for folding inwardly its "lower pocketformingfiap'into adhesive seam connection with the margins of its previously-infolded side flaps.

48. In mechanism for making envelopes from a succession of blanks advancing flatwise, seal flaps trailing, in spaced relation, means for folding inwardly the side flaps of the successive"so advancing blanks, means for-thereafter so slowing down each blanks advance as to produce a shingling or overlap with the next blank that exposes in juxtaposition the seal flap margin of one and the seam forming edges of the others infolded side flaps, :rotary glue-imprinting means past which the slowed down so-shingled blanks are moved, and means for operating said glue imprinting means in timed relation to the slowed down movement past same of the so-shingled blanks, for the deposit of a portion of its adhesive on each seal flap margin and for the deposit of another portion of its adhesive along the seam forming edges of the next blanks infolded side flaps.

49. In mechanism for making envelopes, a pair of spaced apart blank forwarding sections -for the-highspeed movement of successiveblanks in spaced'relation,

the-first said sectidnhaving means for folding inwardly the side flaps of the so-spaced blanks, and the second said section having means for folding inwardly each blanks back or bottom flap, to overlap-margins of its previously infolded side flaps, a low speed blank'forwarding section between said two high-speed sections, for progressively'collecting and forwarding the succes- 'sive blanks, with side flaps infolded, in a shallowly shingled assembly which exposes each blanks said side-flap margins in close' proximity to the adjacent blanks seal flap margin, anda glue imprinting device, rotating in step with the relatively low speed imparted to said shingled blank assembly by said low speed blank forwarding section, for'imprinting withglue each seal-flap and the adjacent edges of the so-exposed side flap margins of each blank, before the latter is separated from said assembly by said second high speed blank-forwarding section.

References Cited in the file of this patent UNITED STATES PATENTS 1,121,126 Novick Dec. 15, 1914 1,943,985 Novick Ian. 16, 1934 1,985,859 Goder Dec. 25, 1934 2,087,345 Heywood July 20, 1937 

